Switch.



R. (LAWYER & J: D. GATTISQ SWITCH. APPLIUATION FILED JAN. 14, 1911.

Patented Sept. 19, 1911.

BWE WJMH HOS-(30E GAVJYER AND JAMES I). UATTIS, 1'.C[ERGU1R.Y,

matters 121 tent.

Serial No. 602

S'WITCH.

" ation of Specizc ipu'iiuatiozl fileii January 1 1111' Fri.

post 21 to Which the bell circuit wire B is connected. The binding post21 to which the telephone circuit wire T is connected is also Wired tothe binding posts '16 and 17 g as indicated at 0, respectively, whilewires (1, (Z connect the binding posts 21 with the posts-16 and 17respectively. The bind ing post 16 is connected by means of the circuitwire 0 with the contact member 12 and the binding post 17* is connectedby means of a wire 6 with the contact member 11. Awire f connects thebinding post 16 to the, contact member 11 and a wire f also connects thebinding post 1.7 to the contact connected in. the bell circuit only.Therefore it will be seen that when the switch blade is depressed in theabove manner, the tclcpl'ione circuit is broken through the contactmembers 11, 12 and 13 and the switch blade. The connection is madebetween the subscribers telephone line 'l and the party line Vi throughthe wire 0 which connects the binding post 521 and the binding post 16,from whence the current is conducted by the Switchblade 6 throughbinding pest 1.6, wire f, binding post 11, and wire a to the bindingpost 20 to which the wire i is connected. The line W" is thusdisconnected from the talking circuit of the telephone but is connectedin the bell circuit through binding post 21, Wire 0?, binding post 16,conducting wire 19, binding post 16, wire 6, binding post 12 and wire a.It will be obvious that all. parties on the wire W are disconnected fromthe talking circuit so that the conversation carried on between thesubscriber and the party calling over the line W cannot be overheard.The line lV may be connected in the telephone circuit While the line Iis only included in the bell circuit by simply reversing the aboveoperation and depressing the button 7 at the right hand end of theswitch blade.

From the-foregoing it is thought that the construction and operation ofour improved telephone switch will be readily understood.

The device is comparatively simple in construction and eavesdroppingupon telephonic conversation carried on over party telephone lines isrendered absolutely impossible. Such a switch is of great couvenience intelephone lines of this character which are widely used 1n ruralcommunities.

Such a switch may be constructed at a nominal cost and readily installedin telephone systems of the present construction. lt may also be easilyand quickly operated and is highly eflicientand reliable in practicaluse.

While we have shown and described the preferred construction andarrangement of the various parts, it will be understood that the deviceis susceptible of considerablemodification without departing from theessential feature or sacrificing any of the advantages thereof.

Having thus described the invention what is claimed is 1. In a switch ofthe chara ctcr described, the combination with a party line telephonecircuit including a main line circuit and a bell circuit, of a. springheld dcpressible switch blade, contacts normally engaged by said switchblade to close the bell. circuit, contacts arranged in each of saidcircuits, and means carried by,thc switch blade to engage certain ofsaid. contacts and maintain the bell circuit closed, said switch bladeongagii'ig other of the contacts to close the telephone circuit through.the party line.

2. In a switch of the clmraclcr described, a telephone circuit includinga party circuit. having two line wires and a bell circuit, in cmibination with a switch comprising contact members each wired to one ofthe party line wires, a. contact member wired to the bell circuit,binding, posts wired to the first named contacts and to the localtelephone line, a movable SWll'.Cl'l blade, a. spring yicldingly holdingsaid blade in mi 'auenunt with the contacts to normally close the bellcircuit through the party lines-1, two series of contacts each wired. tothe bell. and line circuits, and m ans arranged upon each end of theswitch blade whereby when the end of said blade depressed the talkingcircuit is connected through one of the party line wires and the bellcircuit through the other party line wire.

3'. In a switch of the character described, a telephone circuitincluding a party talking circuit having two line wires and a, bellcircuit, contacts wired to the party line, a contact wired to the bellcircuit, a switch blade provided with a central longitudinal slot. apost extending through said slot, a spring on said post bearing againstthe blade and normally holding the same in engagement with the contactsto close the bell circuit through the. party lines, a series of bindingposts arranged beneath each end of the switch blade, said post beingwired to the party line and bell circuits, a bridge member of insulatingmaterial I end oi the switch blade, an electrical conductor fixed tosaid bridge member for engagement with certain of the binding posts,whereby upon th'elldepression of thd switch arranged on each blade atone en'd' e talking circuit is connected through one of the line wiresby the our signatures in the presence of two witengagement of the switchblade with certain nesses.

of the contacts, and the bell circuit is con- ROSCOE CAWYER.

nccted through the other of the line Wires by JAMES D. GATTIS. 5 theengagement of the conductor With t-he Wit s remaining contacts. HAM. E.MCBRIDE,

In testimony whereof We hereunto affix EVERETT O. ROBERTSON.

